aggravation

I'm in the middle of replacing the clutch master cylinder...what a place to hide that thing!
Anyway, should I put some teflon tape on the threads for the hard pipe that connects to the master itself as well as the hard pipe I took loose from the slave to the master? I didn't see any sign of thread tape or other sealer but I sure don't want to close everything up and have a leak there! Once I button this up I don't want to have to re-visit this device for many miles!

WallyP

I would never allow any teflon tape on any plumbing connection on any of the race cars - nor on any cars that I work on. I don't like the chances of a sliver of teflon getting into somewhere that it shouldn't be...

I use a teflon paste pipe sealant.

blown 87

John Veninger

What Wally said!

aggravation

Roger that!
Just for clarity's sake, are you recommending a teflon paste for the particular connections I asked about or just saying you generally prefer paste over tape?

hacker-pschorr

I changed mine this past summer, I didn't use anything on these threads. No leaks yet.

Mrmerlin

Hi No sealants are needed to seal the pipe fittings the only thing i would suggest is that you use some antiseize on the pipe to collar nut this will help it not to rust together and then fracture in 10 years when you replace the the master again, only use a small amount of antiseiz on the pipe, Stan

dr bob

What MrMerlin said...

The fittings on the brake and clutch lines are double-flared tube fittings, where the "sealing" is done by the tapered inside of the tubing flare against the little conical protrusion in the cylinder. The nut applies pressure to help the seal and keep it aligned, but does none of the sealing itself. A tiny bit of Never-Seeze on the thraeds of the nut may help in future removals, BUT... Make sure that no anti-sieze gets into the tube or the seat or has a possibility of contaminating the fluid. The oil carrier in the rubber brake parts causes problems. So, no tape, no thread sealants. If you have a leak that won't quit, it may be time to replace the line or perhaps cut it and re-do it with the --proper double-flaring tool--. This is not done with the flaring tool you buy at Home Depot in the plumbing dept, but requires a specialized tool set made for the task.

aggravation

Thanks!
The fittings looked a bit foriegn to me, i don't usually work on automobiles. I'm an A/C and Refrigeration contractor by trade and the fittings looked like something I wouldn't put a sealant on, When not brazing I typically use either regular flare or compression fittings, neither of which would require sealant, these were a bit different though and I didn't want to neglect an important step before installing the master cylinder.

928 Specialists has backordered my Motive PowerBleeder so I built a power bleeder out of a garden variety pump up sprayer and a spare cap for a gasoline powered edger that happens to fit the reservoir on the 928 nearly perfectly (a temporary solution, I'll still take delivery of the real thing once it ships).

I pumped it up dry to 12 psi after installing the master cylinder and used an ultrasonic leak detector on all the connections, no sound=good seal, so now I just need to bleed the air out with some new fluid....

dr bob

I built a home-brew power bleeder out of a garden sprayer years ago, and it works just great. If you have something that works, no need to spend $$ on the Motiv. Reality is that mine comes out once a year for my car and a few other times for guests' cars, and otherwise takes up shelf space. No need to take up two shelf spaces almost all the time.